High-gamma band fronto-temporal coherence as a measure of functional connectivity in speech motor control. (1st October 2015)

• Record Type: Journal Article
• Authors: Kingyon, J.; Behroozmand, R.; Kelley, R.; Oya, H.; Kawasaki, H.; Narayanan, N.S.; Greenlee, J.D.W.
• Is Part Of: Neuroscience. Volume 305(2015)
• Page Start: 15
• Page End: 25
• Publication Date: 2015-10-01
• Subjects: CFC cross frequency coupling -- dPMC dorsal premotor cortex -- ERBP event-related band power -- HGE hybrid depth electrode -- IFG inferior frontal gyrus -- STG superior temporal gyrus; auditory cortex -- premotor cortex -- LFP -- speech -- efference copy -- ECoG; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2015.07.069
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: We study the neural basis of human speech using intracranial electrophysiology. We show high-gamma band coherence (70–150 Hz) between frontal and temporal regions. High-gamma band coherence is stronger when patients were vocalizing. These results provide evidence of sensory–motor coupling during speech. Abstract: The neural basis of human speech is unclear. Intracranial electrophysiological recordings have revealed that high-gamma band oscillations (70–150 Hz) are observed in the frontal lobe during speech production and in the temporal lobe during speech perception. Here, we tested the hypothesis that the frontal and temporal brain regions had high-gamma coherence during speech. We recorded electrocorticography (ECoG) from the frontal and temporal cortices of five humans who underwent surgery for medically intractable epilepsy, and studied coherence between the frontal and temporal cortex during vocalization and playback of vocalization. We report two novel results. First, we observed high-gamma band as well as theta (4–8 Hz) coherence between frontal and temporal lobes. Second, both high-gamma and theta coherence were stronger when subjects were actively vocalizing as compared to playback of the same vocalizations. These findings provide evidence that coupling between sensory–motor networks measured by high-gamma coherence plays a key role in feedback-based monitoring and control of vocal output for human vocalization.